Recidivist violent prisoners incarcerated on indeterminant sentences at Patuxent Institute will be studied utilizing unique clinical, psychometric and EEG activation techniques that have proven useful in psychiatric clinics and hospitals. Differentiation on the basis of clinical data will be made between subjects with aggressive "life styles" and those manifesting episodic (impulsive) aggression. In the latter group a further differentiation will be made between epileptoid and hysteroid (motivated) impulsivity. One hypothesis to be tested is that chloralose activation of the EEG will correlate positively with the epileptoid impulsive subjects. Data will be collected in such a way as to determine the reliability of the psychiatric, psychometric and EEG measures of epileptoid and motivated impulsivity allowing for computer analysis of both the psychologic and electroencephalographic data. Finally, the clinical usefulness of the procedure will be tested in a double-blind study utilizing the anticonvulsant primidone (Mysoline) as the therapeutic agent, and comparing these results with a previous study in the same setting utilizing diphenylhydantoin (Dilantin).